<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"> 
<title>菜鸟教程(runoob.com)</title> 
<script src="https://cdn.staticfile.org/jquery/1.10.2/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $("button").click(function(){
        $("#runoob").attr("href", function(i, origValue){
            return origValue + "/jquery";
        });
    });
});
</script>
</head>
<body>

<p><a href="http://www.runoob.com" id="runoob">菜鸟教程</a></p>

<button>修改 href 值</button>

<p>点击按钮修改后，可以点击链接查看 href 属性是否变化。</p>

</body>
</html>